Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990)
| | Revised descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990) |
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  (Pl. 8g): holotype, GS9508, J40/f8803, McCulloch's Bridge, Kaiatan (TM4927, GNS) |
Beu & Maxwell (1990): Chapter 8; p. 121; pl. 8 g.
Synonymy: Poirieria denticulifera Maxwell 1971, p. 773
Classification: Muricidae: Muricinae
Description: Rather small for genus (height 17-22 mm), biconic, spire about 0.3 total height. Protoconch narrowly conical, of about 4 lightly convex whorls. Teleoconch of 4.5-5 whorls, bluntly shouldered near middle on spire, last whorl contracted to moderately long neck. Axial sculpture of 5 or 6 thin, low varices on each whorl, folded into prominent, open triangular spines on shoulder; varices on last whorl bearing a much smaller triangular spine near junction of base and neck. Spiral sculpture of weak threads on base of last whorl. Aperture pyriform, constricted abapically to form a moderately long, straight siphonal canal. Inner lip thinly callused, smooth; outer lip slightly flared, with 5 weak denticles within. Fasciole prominent, with a small pseudumbilicus between it and canal.
Comparison: Poirieria denticulifera is distinguished from other New Zealand species of the genus primarily by its denticulate outer lip and secondarily by its small size and the presence of only one spine on each varix in addition to the peripheral spine. P. parva Maxwell, 1971 (Otaian-Altonian, Northland) is similar in size to P. denticulifera, but apart from having a smooth outer lip, it differs in having three or four small accessory spines on each varix.
Poirieria (sensu stricto) is first recorded from the Bortonian in New Zealand, and seems to have been present in the Northern Hemisphere during the Paleocene and Early Eocene (Maxwell 1971, p . 764; Vokes 1971b, p. 37). The genus is a relatively "primitive" and conservative member of the Muricinae that presumably was once widespread, but it is now restricted to the New Zealand region, although a number of species from elsewhere have been referred here tentatively, and in other subgenera. New Zealand occurrences were reviewed by Maxwell (1971).
Distribution: Bortonian- Kaiatan, Whaingaroan?; Kaiatan, Waihao Greensand, McCulloch's Bridge (type); Waihao Downs; Kakanui (?). Rare at all localities.
Cite this publication as: "A.G. Beu and J.I. Raine (2009). Revised
descriptions of New Zealand Cenozoic Mollusca from Beu and Maxwell (1990). GNS
Science miscellaneous series no. 27."
© GNS Science, 2009
ISBN
978-0-478-19705-1
ISSN 1177-2441
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